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Jon Gosselin doesn't know his son's Collin's whereabouts. The father of eight claims he hasn't seen his 12-year-old son over a year and a half and his ex-wife Kate Gosselin won't tell him where Collin is. "I have an idea where he is, but I don't really know where he is," he says.

Jon further tells ET Online, "I mean, I ask but she doesn't tell me. She doesn't answer any of my texts." He reveals that Collin's brothers and sisters are also clueless about where Collin is. "They know that their mom told them that he has behavioral issues," he says.

According to Jon, Kate "says that Collin is in a special school for special needs kids with behavioral problems," but he has been told otherwise by law enforcement officials.

Jon shares that the last time he saw Collin, he seemed fine. He describes Collin as an intelligent child. "I could see my kids getting annoyed with that because he's the smartest and he does this, and he does that, and he always wants it his way," he says. "He's very particular, which could be bothersome. But, he's very loving too. He was a cuddly kid as a baby."

Kate currently has full legal custody of their kids, while Jon has partial physical custody. Jon has planned a legal action to get a judge to force his 41-year-old ex-wife to tell him where his son is.